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| SAFETY WARNING
Concerns the lineGrip G2 ONLY!!! >>>>
(All devices which were shipped before September 2010) |
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The following safety relevant issues are currently known:
1. Rubber coating slipping on the webbing above 30°C at over 17kN
2. Peeling rubber coating above 30°C and over 16kN
Important notice:
>>> Updated per 30.11.2010
Evaluation of the ideal compound for the series-03 clamping jaws is complete and production is running. The new clamping jaws will be available early December. These rubber coatings are vulcanized, just like the series 02 (NOT glued, explanation see message 1 below), only the compound has changed.
Of course, each series 01 and series 02 lineGrip owner will be sent a couple of series 03 clamping jaws free of charge, including a special tool, for self replacement. The replacement is a matter of 2-3 minutes.
1. Rubber coating slipping on the webbing
Concerns lineGrip series 02a (Dispatched from Mai 21 2010)
The rubber coatings of series 02a were directly vulcanized to the aluminum block, due to under certain circumstances peeling off of the glued series 01 rubber coatings. This means that a ductile natural rubber compund is heated to 160° C and is permanently vulcanized to the aluminum block under very high pressure. This bonding is mechanically stronger than the rubber itself and can never be separated - the rubber and aluminum are inextricably joined.
Unfortunately, a small error has slipped in on the series 02a rubber compund (the first series which was vulcanized). These rubber coatings might slip slightly on the webbing (the slackline) at over 30°C, dry air and more than 17kN tensile force. It depends heavily on the type of slackline used, or how the surface is roughened. On almost brand new or unused and on very tightly woven webbings, the risk of slippage is greater than on used and coarsely woven webbings.
Note: This effect was only discovered and verified by us in our laboratory. So far, no case is known in which this effect occurred during the tensioning of a longline. Nevertheless, we advise all lineGrip series 02 owners to adhere by the following precautions:
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lineGrip series 02a safety notice:
(sent by email to all lineGrip-22 owners on June 25, to all lineGrip-15 owners on July 23 2010)
above 30°C and dry air it may occur that the linegrip slips slightly on the webbing at more than 15kN of tension. although this effect was not observed below 30°C, it can not currently be excluded 100%!
this effect was only discovered and verified by us in our laboratory. so far, no case is known in which this effect occurred during the tensioning a longline.
we nevertheless advise you to adhere by the following precautions until the causes of this issue are clearly identified and we can offer you a solution in order to prevent this effect:
1. above 30°C ambient temperature do not load with more than 13kn!!!
2. until further notice, do not expose to direct sunlight, if the linegrip might heat up to over 30°C (cover with towel or tshirt)!
3. always backup while tensioning using a suitable line locker (linehook, slackbanana, slackdog, linelock, etc.) and regularly pull out the slack inbetween linegrip and locker (every 30-40cm).
4. never use the linegrip as a sole line fixation, or remove the line locker during the tensioning process! should the line begin to slip through certain circumstances it will be stopped by the line locker, before a chain reaction can take place.
should the line begin to slip unstopped under high tension, it might lead to a chain reaction, under which the rubber coating warms up more, the more webbing is gliding through. the warmer the coating, the softer it gets, and the easier the webbing will glide through...
nothing can happen though, if the webbing is backed up in a line locker, beecause the linegrip never lets go of the line abruptly. it always begins with a subtle slipping.
we are working hard to identify the source of this issue and be able to eliminate it. until then we kindly ask for a little patience. for your personal safety please adhere to the above precautions until further notice, while using the lineGrip at over 10kn (for safety reasons we recommend to always heed the pts. 2-4 anyway)
please remember to inform anyone using your linegrip about these issues, thank you!
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2. Peeling off of rubber coating
Concerns lineGrip series 01a and 01b (Dispatched from Mai 15 to Mai 20 2010 - a total of 17 pieces was dispatched, 3 of these to Japan)
The rubber coatings of the series 01 have been bonded to the aluminum blocks in the form of cut 2mm thick rubber mats by a company near Hamburg specializing in rubber bonding. This was done by mechanical treatment of the aluminum surface, applying a primer and subsequent bonding at 140°C and about 1 ton of pressure. This bonding technique is on the cutting edge of technology and marks the best bondage between a finished rubber mat and the aluminum surface.
Unfortunately it has now emerged, that after a while this bond seems to become unstable and may dissolve with renewed heat and extremely high load. This happens in a small number of 6-8 week old clamping jaws that were in regular use and were heated to 35-40°C directly before or during exposure to over 16kN of tensile force.
So far, one case is known from Berlin, where the rubber coatings have failed and the slackline including rubber pads were pulled out of the lineGrip at over 15kN of tension. The precise circumstances and exact conditions under which it came to this failure are still determined and the lineGrip and the affected section of the slackline have yet to be analyzed. Once there is certainty, this will be published here. It is certain by now, that this happened at over 30°C and above 15kN tensile force - despite all the warnings!
We strongly advise all lineGrip series 02 owners to adhere by the following precautions:
lineGrip series 01 safety notice:
(sent by email to all lineGrip-22 owners on June 15 and July 27, to all lineGrip-15 owners on July 23 2010)
above 30°C it may occur that the bonded rubber coatings may peel from the aluminum block at more than 15kN of tension. although this effect was not observed below 30°C, it can not currently be excluded 100%!
so far, one case is known from berlin, where the rubber coatings have failed and the slackline including rubber pads were pulled out of the linegrip at over 15kN of tension. it is certain by now, that this happened at above 30°C and over 15kN tensile force - despite all the warnings! in our laboratory, this effect could only be verified on a small number of coatings at above 40°C and over 17kN of tension.
we therefore advise you to adhere by the following precautions until the causes of this issue are clearly identified and we can offer you a solution in order to prevent this effect:
1. above 30°C ambient temperature do not load with more than 13kn!!!
2. until further notice, do not expose to direct sunlight, if the linegrip might heat up to over 30°C (cover with towel or tshirt)!
3. always backup while tensioning using a suitable line locker (linehook, slackbanana, slackdog, linelock, etc.) and regularly pull out the slack inbetween linegrip and locker (every 30-40cm).
4. never use the linegrip as a sole line fixation, or remove the line locker during the tensioning process! should the line begin to slip through certain circumstances it will be stopped by the line locker, before a chain reaction can take place.
should the line begin to slip unstopped under high tension, it might lead to a chain reaction in a matter of seconds, under which the bonding and coating warms up more, the more webbing is gliding through. the warmer the bonding, the softer it gets, and the easier the webbing will glide through...
nothing can happen though, if the webbing is backed up in a line locker, beecause the linegrip never lets go of the line abruptly. it always begins with a subtle peeling.
we are working hard to identify the source of this issue and be able to eliminate it. until then we kindly ask for a little patience. for your personal safety please adhere to the above precautions until further notice, while using the lineGrip at over 10kn (for safety reasons we recommend to always heed the pts. 2-4 anyway).
as soon as the series 3 clamping jaws are available, we will send you a pair free of charge including a special tool for self replacement.
please remember to inform anyone using your linegrip about these issues, thank you! |
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